[openib-general] Re: Re: Re: Userspace testing results (many kernels, many svn trees)

[Michael S. Tsirkin]

Quoting r. Grant Grundler <iod00d at hp.com>:
> Subject: Re: [openib-general] Re: Re: Re: Userspace testing results (many?kernels, many svn trees)
> 
> On Tue, Jan 24, 2006 at 08:26:25AM -0800, Shirley Ma wrote:
> > Why not removing the platform dependency and using gettimeofday() instead 
> > to measure the performance?
> 
> The cycle counters can give us transaction level timing.
> We can see how expensive the first/last transactions are
> and what the variation is during the run.
> gettimeofday() can't do that on most platforms.
> 
> AFAICT, only PPC has real wierdness with get_cycles().
> And if that can't be fixed, then we will have to use
> gettimeofday() on PPC or make it a compile time option.
> 
> thanks,
> grant
> 

No, I think I have a sane work-around: run gettimeofday several times
and time it, compare the result with /proc/cpuinfo.

Also good for stuff like power management clocking the CPU down, etc.

-- 
MST